PEEP/DECIDE/GRAPH is an interactive programming system written in SAIL, the Standford Artificial Intelligence Language, and operating on the DCRT PDP-10 computer. PEEP is designed for picture processing applications, DECIDE is intended for algorithmic decision making and exploratory data analysis, and GRAPH has capabilities for two and three dimensional graphics. The system was originally written for the NCI Bladder Cancer Image Processing Project but is of wide utility. In the PEEP system and appendages to it, objects can be obtained from optical density histograms. This option is available in global and local form. Derivatives, Laplacians and Hueckel operators can be applied. A large library of feature extraction algorithms has been built. These features encompass numeric descriptions of size, shape, content, contrast, comparison and orientation. Examples of such features are area, average brightness, diameter, average chord, entropy, kurtosis and skewness of the optical density histogram, integrated optical density, variation in brightness, variation in chord length, variation in diameter, Fourier coefficients of a boundary, bending energy, medial axis transforms, major axis and minor axis. DECIDE enables the performance of parametric and non-parametric recognition of objects. Linear and quadratic discriminant analysis form the basis for parametric recognition. Coefficients of the best discriminant function can be learned from exemplary objects using a learn command. New test objects can be classified into a learned category using the classify command. The user has control over various parameters of the learning process. For example, likelihood maximizing discriminant functions can be developed. Non-parametric recognition is performed by the cluster command. Again, many variations of data normalization, cluster merger strategy and cluster type emphasis are available. GRAPH allows the user to create and display graphic structures in two and three dimensions and to use different vantage points for viewing them. In conjunction with Dr. W. Shoemaker at St. Elizableth's Hospital, morphometric study of synapses of mammalian central nervous systems was undertaken. PEEP was applied to the interactive extraction of neuronal synapse images appearing in specially prepared electron micrographs. Ethanolic ph (Text Truncated - Exceeds Capacity)